Cell-mediated immunity in systemic lupus erythematosus: alterations with advancing age

Area of Science:

• Immunology
• Gerontology
• Rheumatology

Background:

• Cell-mediated immunity (CMI) plays a role in autoimmune diseases like systemic lupus erythematosus (SLE).
• Age-related changes in immune function are well-documented but their specific impact on SLE pathogenesis requires further investigation.
• Understanding CMI in different age groups is crucial for comprehending disease presentation and progression.

Purpose of the Study:

• To compare CMI function in young and elderly patients with SLE and age-matched controls.
• To investigate the influence of age on immune responses to existing and novel antigens.
• To explore the relationship between CMI status and SLE clinical presentation in the elderly.

Main Methods:

• Evaluated CMI using skin tests with pre-existing antigens (PPD, mumps, Candida) and a novel antigen (2-4-dinitrochlorobenzene, DNCB).
• Assessed lymphocyte response to phytohemagglutinin in vitro.
• Compared immune responses across four groups: young SLE patients, elderly SLE patients, young controls, and elderly controls.

Main Results:

• No significant differences in pre-existing CMI or phytohemagglutinin response were observed between the groups.
• Elderly patients (both SLE and controls) showed diminished CMI response to Candida antigen.
• Elderly individuals (SLE and controls) exhibited impaired responses to DNCB sensitization, indicating reduced capacity to respond to new antigens.
• Young SLE patients demonstrated normal CMI responses.

Conclusions:

• CMI appears to diminish with advancing age, irrespective of SLE status.
• The elderly immune system shows reduced responsiveness to novel antigens.
• Impaired CMI in the elderly may contribute to the milder clinical expression of SLE observed in this demographic.
• These findings suggest that age-related alterations in CMI could modify SLE pathogenesis and clinical outcomes.